The present disclosure relates to solar roof tiles. More particularly, it relates to photovoltaic modules and related connector assemblies for effectuating self-supporting installation.
Solar power has long been viewed as an important alternative energy source. To this end, substantial efforts and investments have been made to develop and improve upon solar energy collection technology. Of particular interest are industrial- or commercial-type applications in which relatively significant amounts of solar energy can be collected and utilized in supplementing or satisfying power needs.
Solar photovoltaic technology is generally viewed as an optimal approach for large scale solar energy collection, and can be used as a primary and/or secondary (or supplemental) energy source. In general terms, solar photovoltaic systems (or simply “photovoltaic systems”) employ solar panels made of silicon or other materials (e.g., III-V cells such as GaAs) to convert sunlight into electricity. More particularly, photovoltaic systems typically include a plurality of photovoltaic (PV) modules (or “solar tiles”) interconnected with wiring to one or more appropriate electrical components (e.g., switches, inverters, junction boxes, etc.). The PV module conventionally consists of a PV laminate or panel generally forming an assembly of crystalline or amorphous semiconductor devices electrically interconnected and encapsulated. One or more electrical conductors are carried by the PV laminate through which the solar-generated current is conducted.
Regardless of an exact construction of the PV laminate, most PV applications entail placing an array of PV modules at the installation site in a location where sunlight is readily present. This is especially true for commercial or industrial applications in which a relatively large number of PV modules are desirable for generating substantial amounts of energy, with the rooftop of the commercial building providing a convenient surface at which the PV modules can be placed. As a point of reference, many commercial buildings have large, flat roofs that are inherently conducive to placement of a PV module array, and is the most efficient use of existing space. While rooftop installation is thus highly viable, certain environment constraints must be addressed. For example, the PV laminate is generally flat or planar; thus, if simply “laid” on an otherwise flat rooftop, the PV laminate may not be optimally positioned/oriented to collect a maximum amount of sunlight throughout the day. Instead, it is desirable to tilt the PV laminate at a slight angle relative to the rooftop (i.e., toward the southern sky for northern hemisphere installations, or toward the northern sky for southern hemisphere installations). Further, possible PV module displacement due to wind gusts must be accounted for, especially where the PV laminate is tilted relative to the rooftop as described above.
To address the above concerns, conventional PV module array installation techniques have included physically interconnecting each individual PV module of the array directly with, or into, the existing rooftop structure. For example, some PV module configurations have included multiple frame members that are physically attached to the rooftop via bolts driven through (or penetrating) the rooftop. While this technique may provide a more rigid attachment of the PV module, it is a time-consuming process and permanently damages the rooftop. Also, because holes are formed into the rooftop, distinct opportunities for water damage arise. More recently, PV module configurations have been devised for commercial, flat rooftop installation sites in which the arrayed PV modules are self-maintained relative to the rooftop in a non-penetrating manner. More particularly, the PV modules are interconnected to one another via a series of separate, auxiliary components. One or more wind-deflecting barriers (or “wind deflectors”) are assembled to some or all of the PV modules to reduce (or deflect) a magnitude of wind forces imparted upon an underside of the PV module and/or array. Additional ballast is also oftentimes attached to the array.
In light of the above, the components and techniques employed to interconnect adjacent PV modules are important to the success of an installed, non-penetrating PV module array. In general terms, a typical array consists of PV modules arranged in columns and rows, forming a rectangular grid. By interconnecting the PV modules, each row contributes to the prevention of overturning of an adjacent row. With a rigid connection, the weight/mass of one row resists or offsets the moment force created at the connection point with an adjacent row otherwise being subjected to overturning forces. Each PV module effectively defines four corners; at most locations within the grid, then, four PV modules will come together to define a junction point, and the corners of the PV four modules forming the junction must be joined. However, there will be many instances within an array when one or more of these four PV module corners is “missing”. For example, along the south edge of the array, only two PV module corners will be joined together at the corresponding junction point. With conventional non-penetrating PV module arrays, differing connective components are required to accommodate the various junction configurations (e.g., a first connection device for a four PV module junction and a different, second connection device for a two PV module junction). This, in turn, increases overall costs and installation time, as well as the level of expertise required of the installer. Along these same lines, conventional PV module connection techniques entail the use of one or more hand tools, again increasing installation time and thus costs. Further, metal components are typically used for joining adjacent PV modules; while viable, the metal couplings (and other metal components of the array) raise electrical grounding concerns.
In light of the above, any improvements in the construction of PV modules and associated connecting components for non-penetrating installation as a PV module array will be well-received.